Screen-box for paper-making machines



F.' P. MILLER.

SCREEN Box FOR PAPER MAKING MACHINES.

APPLICATION FILED IAN. 2, 1919.

Patented S6151.; 28, 1920.

4 SHEETS-SHEET I.

F. P'. MILLER,

SCREEN BOX FOR PAPER. MAKING MACHINES.

APPLICATION FILED IAN. 2, 1.919.

1,354,324. Patented Sept. 28, 1920.

4 SHEETS-SHEET 2.

F. P. MILLER.

SCREEN Box FOR PAPER MAKING MACHINES.

APPLICATION FILED IAN- ZI I9I9.

1,354,324, Patent-emph 28,1920.

4 SHEETS-SHEET 3- F. P. MILLER.

SCREEN BOX FOH PAPER MAKING MACHINES.

APPLICATION FILED 1AN.2, 1919.

1,354,324, PatentedSept. 28, 1920.

4 SHEETS-SHEET 4.

fq- L D l 9 AIllllllllllllllllllllllllvlllllll PATENT oFFicE.

FRANK P. MILLER, 0F DOWNINGTOWN, PENNSYLVAIA.

Specication of Letters Patent.' Patented Sept. 28, 1920.

Application led January 2, 1919. Serial` No. 269,228.

To all 'whom it may concern.'

Bc it known that I, FRANK P. MILLER, a citizen of the United States, and a resident of Downingtown, county of Chester, State of Pennsylvania, have invented certain Imrovements in Screen-Boxes for Paperaliing Machines, of which the following is a specification.

The main obj ect o'f my invention 1s to 1mprove the means for operating the suction mechanism of a screen box of a paper making machine, whereby the screens 4can be arranged side by side and at different levels, and operated directly from a slngle shaft extending transversely through the several screen structures. i

A further object of the invention is to .relievethe power mechanism of the weight of the suction boxes.

A still further object of the invention is to provide a' rocking means for actuating the screen boxes.

The invention relates also to further details which will be described hereafter.

'In the accompanying drawings Figure 1, is a planview of a series of screen boxes, illustrating my inventionand showing them connected to the vatsof a paper making machine;

ig. 2, is a front view of the screen boxes showing them arranged on different levels;

Fig. 3, is a sideview lookingv in the direction of the arrow 3,- Fig. 1;

Fig. 4, is a side view of one of the screen boxes;

Fig. 5, is a plan view of one of the screen boxes;

Fig. 6, is an end view;

Fig. 7, is a diagrammatic view showlng the connection from the driving shaft to the several rockers which operate the suction devices;

Fig. 8, is a detached view of the cam shaft;

Fig. 9, is a sectional view of a portlon of the screen box, showing one of the suction devices; and l Fig. 10, is a View illustrating a modification of the invention.

1, 1 are the screen boxes, six inthe present instance, arranged side by side, and 2 is a separate box for receiving material from the other boxes and re-screening it. The material passing through the screen boxes 1 is discharged through pipes 8 to the pumps 4, which in turn connect with pipes 5 leading to the vats 6 of a paper making mach1ne. Thls machine is of the ordinary construction and the vats are arranged at dliferent levels for the purpose of allowing the couch roll to be so located that the water will flow back into the vat as the paper is being formed.

It is of advantage to have the screen boxes at a certain level above the vats, and I have found that by arranging the boxes on levels corresponding to the levels of the several vats I obtain a more even flow of material from all of the screen boxes to the vats and, consequently, a much better grading of the pulp is the result thanl if the height of the screen boxes in respect to the vats is varied.

Heretofore to accomplish this it was neces sary to independently drive the mechanisms of each of the screen boxes, and it was the common practice to arrange them end to end rather than side by side and to mount on each box a longitudinal shaft and drive these individual shafts from` a long counter shaft By my invention, however, I am enabled to arrange the boxes side by side, taking up a comparatively small amount of space, and I drive the mechanism from a single shaft 7 ruiming transversely through the series of boxes, and this shaft is made up of a series of sections connected together by couplings 8 at the spaces between the several boxes, as clearly shown in Fig. l. This shaft is driven from a belt whichpasses around a belt wheel.9 on one end of the shaft 7 The pump shaft 10 is driven by a belt in thev present instance, and is made up of a series of sections passing through the several pumps 4, and these sections are connected together by couplings, as shown by dotted lines in Fig. 1. i

By the above arrangement any one of the screen boxes can be uncoupled and entirely removed, if necessary,

the sections of the remaining boxes, if necessarv.-

ach box 1, as shown in Fig. 4, is mounted on standards 11 and connected by a cross piece 12 on which are bearings 13 for the pivots 14- ofthe three-armed rockers 15. There' are two of these rockers in the presand replaced, or a" short coupling shaft may be used to connect ica shaft 7. The shaft is mounted in bearings 24 secured to the standards 11 of the several screen boxes.

It will be noticed, in referring to Fig-2,

that the several boxes are arranged on dif=\ ferent levels and in order to connect the several bars 2O to eccentrics on the shaft 7 and to have the same amount of throw on all ofthe suction devices, I gradually raise the pivot 25 equal to the level of the several screen boxes so that, while each device is rocked independently, the rocking action is y the same on all boxes, see Fig. 7. l

It will be noticed that the weight of the suction devices is taken by the beam 12 through the bearings 13 on which the pivots' 14 of the rockers are mounted, and that one suction device of each set balancesthe other. Heretofore it was theusual practice to opcrate the suction-boxes by ca mson longitudinal shafts, the cams taking the full weight of the suction devices aswell as operating them. This made it necessary to frequently renew the bearings and also to renew the cams, but by the construction shown the pivot takes the weight and there vis very little power required to operate the suction devices, as one device balances the other.

Each box has a screen 25, preferably made in sections; the perforations in the screen may be of any size desired dependingupon the character of paper being manufactured. The suction devlces 17 are located under the screens and are constructed in the present instance as shown in Fig. 9. The bearings 16 are attached to heads 26; each head is located in an opening 27 in the bottom of the screen. box and a sheet of rubber 28, or

other suitable material, is secured to the bottom and to the head as shown, and as the compartments 29 underthe screens .25 are separated one from another the short vertical movement imparted to the head will be sufiicient to draw the paper stock of a certain fineness through the screens while the remaining stock is carried forward by flights 30 on endless chains charged into a trough 32. The material flows through this trough to the screen 2, where it is re-screened.

The chains 31 pass around sprocket wheels 33 and 34 mounted onl shafts 35 and 36, respectively, and inthe present instance the shaft 35 is a driven shaft having a gear wheel 37 thereon which meshes with a pin- 31 and dis-k ion 38 on a shaft 39 driven from an over- -devices in each screen box, it will be understood that a single pair can be used without departing from the invention, and while I 'have shown two three-armed rockers and a .connecting bar which 1n turn 1s connected.

to the eccentric rod, the construction illustrated in Fig.l 10 may be/ used, inwhich two two-armed rockers 15 are shown and in which one of the arms is extended as at 18a and connected by eccentric rods-22l to eccentrics on the shaft 7". In this instance the suction ldevices are also balanced.

It will be seen, therefore, by the above description that I am enabledto drive the suction mechanism of a series of screen lboxes from a single shaft extending transversely under Vthe suction boxes, and'to balance the severalv suctionv devices and mount them on a pivot supported by the frame of the machine so'as to relieve the driving mechanism from a material portion of the weight and consequentl reduce the power necessary for operating t e screen boxes.

v1. The combination in a paper making machine, of a series of screen boxes each having independent suction mechanism, said lboxes being arranged at different levels and located side by side; a shaft extending under the several boxes and having an eccentric at each box and an eccentric rod coupling leach eccentric to a suction mechanism.

2. The combination of a series of screen boxes arranged at different levels and located side by side, each box having suction mechanism; a shaft common to all of said boxes and made in sections, the coupling of the sections being located between the boxes; an eccentric on each section; and a rod coupling each`eccentric to one of the suction mechanisms.

3.- The combination in a screen box, of twothree-armed rockers, each rocker having a pivot; bearings for the pivots; suction devices; two of the arms of each rocker being connected to the suction devices; a rod connecting the `other arms ofthe rockers; a driven shaft.; an eccentric therein; and an eccentric rod connecting the eccentric to the tion devices; a connecting rod attached to the third arm of each rocker; the screen boxes being arranged at different levels; a

shaft extending transversely under the several boxes and having eccentrics thereon; and eccentric rods coupling an eccentric with the connection of each screen box.

5. The combination of a series of-screen boxes arranged side by side; screens in each box; suctiondevices also in each box; end.- less chains and flights thereon arranged to control the flow of material over the screens; a single shaft extending past the several boxes; and means for driving the endless chains of the several boxes'from said shaft.

6. The lcombination of a series of screen boxes; screens and suction mechanism therein; means for controlling 4the low of the material over the screens; and a trough common to all of said boxes to receive the material from each box which neeyds re-screenlng. e l

7. The combination of aseries of screen boxes; screens and suction mechanism therein; means for controlling' the How of the material over the screens; a trough common to all of said boxes to receive the material from each box which needsre-screening; anda re-screening box at one end of the series of boxes and"having bearings; two rockers for 'p each screen box; a connecting bar connecting the rockers of eachscreen box; an eccentric on the shaft at each box; and a series of rods y connecting 'the eccentrics With said bars.

9. The combination of a series of screen boxes arranged at different levels and locatedV side by side; a longitudinal shaft extending under all the boxes, each box having suction devices; two three-armed rockers, each rocker being connected to the suction devices; a bar to which the third arm of each rocker is connected, each bar having a depending portion; an eccentric on the shaft at each suction box; and an eccentric rod coupling the eccentric with the depending portion of each-bar,- the pivots for the rods being located at different points on the bar according to the level of the screen box.

In Witness whereof I affix my signature.

FRANK r. MILLER. 

